Physical characterization of light-dependent resistors as dosimeters in radiotherapy
DOI:
https://doi.org/10.37004/sefm/2024.25.1.005Keywords:
Radiotherapy, dosimetry, light-dependent resistor, dose rate, angular responseAbstract
The quality control of radiotherapy treatments relies on the use of dosimetric sensors. Currently, ionization chambers and solid-state diodes, along with electrometers as reading systems, are the most commonly used systems for this purpose. This study investigates new dosimetric systems manufactured from commercial electronic devices, significantly reducing costs by not being specifically designed for use in radiotherapy. In particular, various models of commercial light-dependent resistors (LDRs) were analyzed as an alternative to existing dosimetric systems for dosimetry. A characterization of the response to ionizing radiation was conducted for different commercial models of LDRs associated with a clinical electrometer. Irradiations were performed under the usual conditions of radiotherapy treatments. Experimental results show that these LDR models can serve as an alternative to currently used dosimetric sensors, with the advantages of high sensitivity, smaller size, lower economic cost, and requiring lower polarization voltages.
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